Text A. What is inorganic chemistry?

We hear about organic mostly in terms of food, where it means that whatever you're about to eat was grown without the use of pesticides. But in chemistry, the word organic means you're dealing with carbon compounds. Carbon is an element that is present in all forms of life and is the fourth most abundant element in the universe. Organic chemistry is basically the study of carbon-hydrogen bonds. Inorganic chemistry, on the other hand, is the opposite. It is the study of the formation, synthesis, and properties of compounds that do not contain carbon-hydrogen bonds.

There are around 100,000 known inorganic compounds, while there are around two million known organic compounds. Examples of inorganic compounds include:

· Sodium chloride (NaCl): used as table salt;

· Silicon dioxide (SiO₂): used in computer chips and solar cells;

· Sapphire (Al₂O₃): a well-known gemstone;

· Sulfuric acid (H₂SO₄): a chemical widely used in the production of fertilizers and some household products such as drain cleaners.

Common applications of inorganic compounds: A) Table salt. B) Integrated electronic circuits. C) Jewelry. D) Drain cleaners.

Inorganic compounds can be classified as acids, bases, salts, and oxides.

Acids.

Acids are compounds that produce H+ ions when dissolved in water. Examples of acids include sulfuric acid (H₂SO₄), hydrochloric acid (HCl), hydrofluoric acid (HF), nitric acid (HNO₃) and phosphoric acid (H₃PO₄). Most acids can be dissolved in water and are corrosive, and those that can be ingested have a sour taste. In water, HCl is decomposed in H+ and Cl-

HCl → (H+) + (Cl-)

Bases.

Bases are compounds that produce OH- (hydroxyl ions) when dissolved in water. They are usually found in household products. Some common bases are ammonia hydroxide (NH₄OH), potassium hydroxide (KOH), calcium hydroxide or caustic lime Ca(OH)₂, and sodium hydroxide or caustic soda (NaOH). In water, KOH dissociates in K+ and OH-:

KOH → (K+) + (OH-)

Salts.

Salts are compounds that result from the reaction between an acid and a base. They are ionic compounds formed by two oppositely charged ions (atoms that are not electrically neutral because they have lost or gained one or more electrons). For example, table salt or sodium chloride (NaCl) is formed by the bonding an anion (positively charged ion) and a cation (negatively charged ion): Na+ and Cl-.

Some common salts include sodium chloride or table salt (NaCl), calcium chloride (CaCl₂), magnesium chloride (MgCl₂), and potassium chloride (KCl). Most salts can be dissolved in water to form a solution of the ions. Ions derived from salts like Na+, Mg+2, and K+ are critical for the functioning of the human body. In water, CaCl₂ is decomposed in the following way:

CaCl₂ → (Ca+2) + (Cl-)

Oxides.

Oxides are compounds that contain at least one oxygen atom combined with another element. Oxygen is usually in the form of an anion (O₂-). Transition metal oxides such as titanium (III) oxide (Ti₂O₃) and iron (III) oxide (Fe₂O₃) have useful magnetic and catalytic properties.

 

2. Comprehension check. Read these statements and decide if they are true (T), false (F) or the information is not stated in the text (NS) supporting your answers with necessary information from Text A:

1. Carbon is the most prevalent element in the universe.

2. Inorganic chemistry is the study of the formation and properties of compounds that contain carbon-hydrogen bonds.

3. Some organic compounds can be used in the production of household products such as washing powder or different detergents.

4. Sodium oxide is used as table salt.

5. Inorganic compounds are represented by acids, oxides, and salts.

6. Acids are compounds that produce H+ ions when dissolved in water.

7. Most acids can be dissolved in water and are corrosive, and those that can be ingested have a bitter taste.

8. Bases are compounds that produce hydroxyl ions when dissolved in water.

9. Salts are inorganic compounds formed by anions and cations.

10. Most salts can be dissolved in alkaline solutions.

11. Oxides are compounds that contain one or more atoms of oxygen combined with another element. Oxygen is usually in the form of a cation.